As one of the conventional recording media for audio, video and/or other information, optical discs such as CDs and DVDs, from which recorded information is read using a light beam or to which information is written using a light beam, are widely used. Since such an optical disc is formed from a single plate-like substrate, it can easily be handled and has a larger storage capacity than other recording media such as magnetic tapes, etc. Therefore, the optical discs are widely used as media for recording audio and video information, computer-processed data, etc. Recording media for audio, video and/or other information, such as CDs and DVDs are e.g. known from U.S. Pat. No. 5,541,910, U.S. Pat. No. 5,864,534, U.S. Pat. No. 6,002,663, U.S. Pat. No. 6,252,842 and US 2002/0034154 A1.
Information processing units, such as computers, CD/DVD players, digital cameras and video cameras, have been designed more and more compact with an increasingly smaller internal space of installation for a recording and/or reproducing apparatus using an optical recording medium such as an optical disc or the like. Accordingly, optical discs are also known in the prior art, e.g. from US 2004/0228263 A1, which only have a diameter of 65 mm or less.
US 2004/0228263 A1 discloses an optical disc having a thickness of only 0.4 mm to 0.7 mm, i.e. significantly thinner than conventional optical discs which have a thickness of about 1.2 mm. Such optical discs are also called light weight optical discs (LODs) or thin video discs (TVDs). With this measure it is achieved to reduce the amount of material which is necessary for manufacturing an optical disc and thus to significantly reduce the manufacturing costs. However, in the area around the axis of the optical disc described in US 2004/0228263 A1—the so called clamping are—, the substrate has a thickness of 1.2 mm, because this distance is prescribed for conventional recording and/or reproducing devices (e.g. drives for computers or CD/DVD players). However, the optical disc disclosed in US 2004/0228263 A1 has the drawback that the physical and optical properties are not satisfying. As a result, this optical disc is not a reliable recording medium.